Axial compensators are used to compensate for thermal elongation of the pipeline for all types of laying. Axial expansion joints are characterized by low weight and small dimensions.
The selection of an axial bellows compensator does not require special strength calculations and is carried out according to the compensating capacity, which should cover the linear thermal elongations of the pipeline section with a small margin.
In the event that the compensating capacity of one compensator is not enough to compensate for the calculated thermal elongations — several axial expansion joints are installed in series on the pipeline.
The increase in the length of the pipeline section during thermal expansion is determined by the formula:
dL = a · l · (tmax – tc), mm
a – coefficient of linear thermal expansion, °C-1, its value depends on the physical properties of the material.
tmax - maximum temperature of the hot-water in the pipeline, °C.
tс - ambient temperature at the time of pipeline installation, °C.
l - pipeline section length, m.